keach: it took nearly 4,000 years. but around 3500 b.c., in a culture known as sumer, the world's first cities emerged. now, a more complex economy required more complex record-keeping. accountants took a ball of clay which they poked inside with the fingers to make a cavity. you know, it's just like a tennis ball of clay or even smaller. and once they had a good cavity, they would put inside tokens, and then a flap would be put on top, and all of this was closed. and we are in pre-writing time. and at that time every sumerian had a seal. and when the stone is pressed onto the surface of the envelope, it leaves then a design which is then the mark of the person or the administration involved. keach: with these seals, up to four parties could sign a transaction. these envelopes could hold several tokens securely. but there was no way to know the contents until accountants began to press the tokens into the clay before dropping them inside. the system quickly evolved. it did not take a long time for these accountants to

keach: mr. sakkout is employed by market officials.he occasionally serves as auctioneer if asked, but in the main, his job is to settle disputes. everyone in the fez tanning industry is dependent upon others. the man who dries the finished skins cannot function without those who remove the hair, or without any of the other specialists in the trade. with so many dependent upon forces outside their control, new institutions inevitably develop. in fez, every specialty within the tanning industry has its own guild or craft association. the guilds serve their members by setting standards, restricting membership and controlling prices whenever possible. but perhaps more importantly, guilds represent the interests of their members before various authorities. sometimes this means catering to the public relation needs of the government. steward of the tanner's guild is sherrif mohamad alaoui. interpreter: if the king is coming or if someone from america or france is coming, we are asked to go out and show our happiness, our appreciation that th

keach: many of these books were discovered by the sixteenth century spanish. they were said to be filled with genealogies, prophesies and religious beliefs. but to the spanish conquerors, they were blasphemous. in 1562, bishop diego de landa ordered them destroyed. "we found a large number of books in these characters, "and as they contained nothing "in which there were not to be seen "superstition and lies of the devil, "we burned them all, "which caused them much affliction." ironically, a book by bishop landa himself proved crucial to the understanding of maya writing. stuart: and in it is everything that he observed in yucatan

chuck, i keach thep thinking th precarious for the democrats. if they lose, they lose control. they need to lose three more out of, what, nine possibilities. anything is possible. and keeping control of the senate, after november. >> look, it is tough. because they have expanded the map, colorado, iowa, six months ago. colorado, iowa, and michigan. were sort of ideas that the republicans had of trying to put the senate seats in play. but they really didn't look like they were going to come together. and now, all three of them, seem very competitive. as competitive as those red state democrats. we knew the red state democrats, that quartet of democrats hageni north carolina, and the good news for democrats, all four, three of the four in particular, are in as good as shape today as they have been since they won six years ago arguably. the bad news for democrats is mark udall is more vulnerable. >> yeah. >> and in, in gary peters has not locked down michigan. so, you know even as democrats have improved those troubled red states in the blue and purple they'll have problems. so th